Process for forming yarns



Patented Aug. 22, 1950 PROCESS FOR FORMING YARNS Robert Burgess, Jn, Noroton, Conn.

' No Drawing. "Application June 3, 1948,

I Serial No. zones This invention relates to the art of making yarn for use in the manufacture of textile fabrics.

' In the usual processes for making yarn from staple fibers, taking the cotton system of spinning and drawn one or more times and are then twisted considerably to form yarn. The above steps are varied, of course, depending on the particular type of yarn being made, but in general it is true that in the case of the manufacture of yarn from staple fibers by the cotton system of spinning, the succession of stages between fibers and yarn includes sliver and roving stages. By staple fibers I means fibers of determinate, relatively short length such as cotton fibers, for example, as distinguished from fibers in the form of continuous filaments of indeterminate length such as silk on various synthetic fibers such as rayon or nylon for example. Theprocess of my invention as hereinafter described is limited to use with staple fibers as above defined which-are susceptible of being doubled and drawn. in the roving stage. ever, in addition to natural staple fibers, I include synthetic or natural fibers originally in continuous filament form which have been cut to staple length, which are customarily formed into yarn by using the cotton system of spinning, as for example the staple rayon fibers now used in the manufacture of so-called spun rayon yarn, for

such fibers may be and customarily are doubled and drawn in making yarn therefrom.

In the sliver stage the strand formed from such staple fibers is exceedingly fragile and tenuous.

Itcannot be wound ona bobbin and cannot be safely handled without danger of damaging or breaking the strand. In the roving stage, however, the strand is considerably stronger and after I known as slubbers, which in addition to drawing the strand, impart a slight twist as the roving is wound on the bobbin. Subsequent doubling and drawing operations are usually performed in fly frames and roving frames, sometimes called in- How- - 2Claims. (01. 51-156) Y termediates, and finally the roving is transferred to a spinning frame where thefinal yarn making steps are performed. Such steps customarily include doubling, drawing and twisting.

In the manufacture-of colored fabrics'it is customary either to dye the fibers before carding (stock dyeing), or todye the yarn before weaving (yarn dyeing), or to dye the fabric after weaving (piece dyeing), and while it has been known that it is possible to dye roving, in practice roving which is to be subsequently used for making yarn is seldom dyed as there has heretofore been no particular advantage in so doing except for special purposes.

Stock dyeing is considerably more expensive than yam dyeing or piece dyeing, and has no advantage over yarn dyeing, for example, if the yarn is to be formed from fibers of a single color. Stock dyeing has been confined for the most part, therefore, to the making of woolen yarn, where it has long been known that very beautiful color effects may be obtained in the yarn, and thereafter in fabric woven therefrom, by mixing or blending .difierent colored fibers, and thereafter forming yarn therefrom by the usual processes. The successful blending of such different colored fibers requires great skill, however, and the practiee has seldom been used in the making of yarn from fibers other than woolen fibers.

Thus, in the manufacture of cotton fabrics, dyeing has been confined for the most part to the dyeing of yarn before weaving or dyeing of the fabric after weaving, and with the exception of woolen fabrics this, is generally true-of colored fabrics. One variation may be mentioned, however. It is known that viscose rayons and acetate rayons react differently to some dyes. For ex- '-ample, viscose rayons will not accept certain dyes which are accepted by acetate rayons and vice versa. In the manufacture of spun rayon yarns, therefore, made from staple fibers, it has been well known practice to mix staple viscose rayon fibers with staple acetate rayon fibers and to form yarn from such mixtures by usual methods. Then the yarn has been subjected to a dye which is accepted by the viscose fibers, for example, but not by the acetate fibers, resulting in a yarn containing a blend of dyed viscose fibers and undyed acetate fibers. weaving in that state. Other'ti nes the yarn is subjected to a second dye of a different color which is accepted by the acetate fibers, but'not by the viscose fibers, thus resulting in a yarn containing-a blend of fibers of different colors, the

viscose fibers beingof one color and the acetate Such yarn is sometimes used for fibers being of a diflerent color. Similar results may be obtained by piece dyeing a fabric woven from yarns containing mixtures of viscose and acetate rayon fibers. Such processes, however, are usually limited to two colors.

It is an object of the present invention to provide a process for making yarns in which during the process of making the yarn, dyed fibers of a given color or colors are added to and blended with undyed fibers, whereby the color of the yarn, which otherwise would be that of the undyed fibers, is modified by such addition. For example, a relatively small proportion of cotton fibers dyed blue might be added to and blended with a larger proportion of undyed cotton fibers in the manner hereinafter described to obtain a pale blue tint in the yarn, in which, however, the appearance of the yarn and of fabric woven therefrom would be quite difierent from an ordinary cotton yarn or fabric dyed a comparable tint of blue.

In the manufacture of synthetic fibers such as rayon fibers, for example, it is now common practice to color the solution or dope from which filaments are to be extruded by the addition of suitable dyes or pigments to the solution, so that the filaments formed from such colored solutions and the staple fibers cut from such filaments are colored. Since such fibersgalthough colored, are not dyed in the usual sense, that is, they are not subjected to a dyeing operation after they become fibers, I shall include them within the term undyed fibers" as used in this specification. As another example, therefore, a relatively small proportion of rayon fibers dyed blue might be added to and blended with a larger-proportion of undyed rayon fibers which had been made from a yellow colored solution, so that the fibers made therefrom would be yellow. The addition and blending of such blue dyed fibers therewith would produce a greenish tint in the yarn, in which, however, the appearance of the yarn and of fabric woven therefrom would be quite different from an ordinary rayon yarn or fabric dyed a comparable tint of green or made from green fibers formed from an appropriately colored solution.

The invention constitutes a, modification of or improvement on the process of making yarns described and claimed in my copending application Serial No. 481.208, filed May 8, 1943, now Patent No. 2.462,842, dated March 1, 19,49 and it is a further object of the invention to provide a simplified process for obtaining blended color effects similar in nature to those described therein, but better adapted for the purposes described herein.

Other objects and advantages of the invention will appear hereinafter.

According to the present invention, with respect to the fibers which are to be dyed, I proceed according to present practices up to the stage where roving is formed, that is, silver is formed from carded fibers, and then by the usual methods of doubling and drawing, together with slight twisting, roving is formed, and wound on ceed according to present practices, but only up to the stage where sliver is formed, and before,

the sliver is twisted to form roving. Such silver 4 is usually. delivered from the drawing'frames into cans.

One or more of the dyed rovings above described are then doubled and drawn with one or more strands of sliver formed from undyed fibers. In the process of doubling and drawing, the fibers of the dyed roving or rovings become intermingled with the undyed fibers of the slivers so that a mixture of the dyed fibers with the undyed fibers occurs throughout the strand.

This initial doubling and drawing of dyed rovings with undyed sliver may be performed on any one of several types of machines commonly used in the cotton system of spinning, provided such machines are suitably modified to allow one or more strands of roving and silver to be fed simultaneously to the drawing rolls thereof. It is a relatively simple matter to adapt any of these machines to feed either sliver or roving or both, but as a practical matter I would prefer to modify a drawing frame to support one or more bobbins so that roving strands may feed therefrom to be doubled and drawn with one or more sliver strands.

If this initial mixing step is performed on a drawing frame, the strand issuing therefrom would be in sliver form, but if the step is performed on either a slubber or an intermediate frame the resulting strand would be twisted and would issue in roving form.

In either case the strand resulting from the initial mixing step is subsequently doubled and drawn with a similar strand or strands to effect a more thorough intermingling or blending of the dyed fibers with the undyed fibers, and this process of doubling and drawing similar strands may be repeated as desired until/finally the strands are fed to a spinning frame and issue therefrom as yarn. In most cases, the usual series of operations as customarily performed in the cotton system of spinning will be sufllcient to produce a very thorough blending of the dyed and undyed fibers. For example, if the initial mixing step is performed in a drawing frame, the

- subsequent operations as usually performed in slubbers, intermediates and spinning frames will be adequate to provide good blending, and this will be true even in cases where, as is now the practice in some mills, slubbers are omitted and slivers from the last drawing frame are fed directly to the first intermediate frame. If the initial mixing step is performed in a slubber, the subsequent operations as usually performed in intermediates and spinning frames will likewise be adequate to provide good blending. 'If the initial mixing step is performed in an intermediate frame, extra intermediate operations will usually be required.

As a specific example of the practice of the process, let it be assumed that it is desired to produce a cotton yarn having a very pale blue tint or hue. For this purpose, the cotton fibers would be subjected to the usual operations of picking, carding, combing if desired, and then would be subjected to one or more drawing frame operations. Some of the sliver strands resulting from the drawing operations would then be put through a slubber, or its equivalent, to form rovings, and such rovings would then be dyed the desired shade of blue.

One or more of such blue rovings, say two, for example, may then be fed to a drawing frame and doubled and drawn with several of the strands of undyed sliver, say eight, for example. The strand of silver issuing from the drawing frame 5 would then consist of a mixture of blue fibers and undyed fibers. Preferably, two or more 0! such strands would then be fed to a slubber, or in some cases directly to an intermediate and doubled and drawn therein to increase the thoroughness of the intermingling and dispersion of the dyed fibers with the undyed fibers. At the same time the strand would be twistedand would issue as a roving. Alternatively, one such strand might be fed to a slubber and drawn and twisted to form roving as this operation would also increase the thoroughness of the intermingling', although not quite to the same extent as when two or more strands are doubled and drawn therein. In either case, two or more of such strands of roving would then be fed to an intermediate frame and doubled and drawn therein, to again increase the thoroughness of the intermingling, and so on, if desired, until the desired intermingling and the desired strand size has been reached. Then two or more strands from the last intermediate frame are fed to a spinning frame to form yarn.

In order to obtain other color eflfects, dyed rovings of other colors or combinations of colors may be combined with slivers of undyed fibers. For example, a strand of roving dyed blue and a strand of roving dyed red might be fed together for blending with several sliver strands, and other combinations of colors may be employed depending on the effect desired.

I claim as my invention:

1. In the cotton system for forming yarn from staple fibers of cotton or rayon, the process of forming yarn in which dyed fibers are intermingled and blended with undyed fibers which comprises forming strands of roving from undyed fibers, dyeing said sfrands of roving, forming strands of sliver from undyed fibers, doubling and drawing at least one of said strands of dyed roving with at least one strand of undyed sliver to form a strand in which the dyed fibers are intermingled with the undyed fibers, thereafter doubling and drawing said strand with at least one other similar strand to increase the thoroughness of the intermingling, and finally spinning said strands to form yarn.

2. -In the cotton system for forming yarn from staple fibers of cotton or rayon, the process of forming yarn in which dyed fibers are intermingled and blended with undyed fibers which comprises forming strands of roving from undyed fibers, dyeing said strands of roving, forming strands of sliver from undyed fibers, doubling and drawing at least one of said strands of dyed roving with at least one strand of undyed sliver in a drawing frame to form a strand of sliver in which the dyed fibers are intermingled with the undyed fibers, drawing and twisting said strand of sliver to form a strand of roving, thereafter doubling and drawing said strand with at least one other similar strand to increase the thoroughness of the intermingling, and finally spinning said strands to form yarn.

ROBERT BURGESS, Ja.

No references cited. 

1. IN THE COTTON SYSTEM FOR FORMING YARN FROM STAPLE FIBERS OF COTTON OR RAYON, THE PROCESS OF FORMING YARN IN WHICH DYED FIBERS ARE INTERMINGLED AND BLENDED WITH UNDYED FIBERS WHICH COMPRISES FORMING STRANDS OF ROVING FROM UNDYED FIBERS, DYEING SAID STRANDS OF ROVING, FORMING STRANDS OF SLIVER FROM UNDYED FIBERS, DOUBLING AND DRAWING AT LEAST ONE OF SAID STRANDS OF DYED ROVING WITH AT LEAST ONE STRAND OF UNDYED SILVER TO FORM A STRAND IN WHICH THE DYED FIBERS ARE INTERMINGLED WITH THE UNDYED FIBERS, THEREAFTER DOUBLING AND DRAWING SAID STRAND WITH AT LEAST ONE OTHER SIMILAR STRAND TO INCREASE THE THOROUGHNESS OF THE INTERMINGLING, AND FINALLY SPINNING SAID STRANDS TO FORM YARN. 